What is the primary function of an underdrain in a filtration system?

The primary function of an underdrain in a filtration system is to support the filter media. Underdrains are typically positioned at the bottom of a filter bed to provide structural support, ensuring that the filter media remains in place during operation. They also play a critical role in evenly distributing the filtered water as it flows downward, preventing the media from becoming overly compacted and ensuring efficient filtration.

In addition to their supportive role, underdrains help to facilitate proper drainage of water from the filter. This drainage process allows for effective backwashing and maintenance of the filter. Therefore, proper design and placement of underdrains are essential for the overall efficiency and longevity of the filtration system.

While measuring water quality, controlling flow rate, and distributing chemicals are all important functions in water treatment processes, these tasks are not the primary responsibilities of an underdrain. Instead, they typically involve other components of the filtration and treatment systems.